Many devices are known and have been developed to assist patients in self-administration of insulin and other medications with hypodermic syringes. The need for such devices arises largely from the psychological difficulty experienced by many patients in striking themselves with a needle. The ideal instrument must be easy to load with a syringe, cause minimal noise in its operation so as not to frighten patients, reduce the discomfort of injection, and any moving part should be so situated or housed as not to interfere with the application and use of the device. In addition, the device should be capable of accepting the syringes of different manufacturers and useful with syringes of different capacities, such as the conventional 1/2 c.c. and 1 c.c. sizes. It is also desirable that the device be capable of adjusting the depth of injection, particularly for children or for persons having thin skin or subcutaneous tissue. The invention herein described is believed to meet all of these criteria and to be an advance in the state of the art.